Bicycle alarm and Airtag case

thingiverse

A no-frills case for "those" well-known bicycle alarms and an Apple Airtag. Mounts onto the bottle holder threads. This case does not have a magic trick for opening and closing but relies on opportunistic thieves not having the required tools on them. Someone who **does** have the tools will still have to endure the alarm for several minutes. Project includes: - top and bottom case - flat anti-leverage shim for my own bike's top tube, which is 100% flat at the bottle holder - An example round-tube shim for 1.25 in / 31.75 mm tubes is included, more will be added to the project on request - Individual shim customization may be required to accommodate offsets around the bottle holder threads Assembly required: - 4x M4 heat-set nuts (soldering iron required, too) - 2x countersunk screws for the mounting holes (probably M5x16) - 4x M4x20 stainless countersunk screws for the top case - A bit of foam or tissue, in case of rattling. Notes: - For drainage, the unsealed seam between bottom and top case, together with the permeability of the material, will have to suffice. - My own case is printed in bright red PLA at 100% infill and uses security screws for the top case. - I suggest less than 100% infill so the tiny amount of PLA displaced by the heat-set nuts has a place to settle. Links: - [Github](https://github.com/mschmitt/bicycle-alarm-airtag) - [Thingiverse](https://www.thingiverse.com/thing:5842363)